I haven’t done much work on 520 for a while because I’m waiting for the ‘call before you dig’ people to do their inspections. They will flag the area for all utilities (gas, electricity, cable, phone, water, sewer). Until that happens, I wait. Until then, I marked the area where the fence will be constructed.
I have a feeling that, under the gazebo, there is a septic tank. Just a feeling. There’s all manner of other junk buried back there.